<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>

        .inter{
            width: 100px;
            height: 100px;
            border: 1px solid gainsboro;
            
        }
        .d1{
            background-color: rgb(40, 189, 55);
            position: fixed;
            top: 100px;
            left: 100px;
        }
        .d2{
            background-color: blue;
            
        }
        .d3{
            background-color: red;
            
        }
        /* 
        position:随着浏览器的变化而变化的
            statci      默认
            relative    相对初始位置不释放文档流
            absolute    绝对
            fixed       相对浏览器窗口定位释放文档流
            left        居然左边多少像素
            right
            top
            bottom
        */
    </style>
</head>
<body>




    
        <div class="inter d1">a</div>
        <div class="inter d2">b</div>
        <div class="inter d3">c</div>






</body>
</html>